Anti Barking Device for Dogs – 3X Ultrasonic Dog Barking Deterrent Devices +
6-in-1 Bark Stopper Modes: Supports fixed (25 kHz) & variable (20–30 kHz) ultrasonic frequencies, plus three training modes — Sound, Ultrasonic, and Ultrasonic + Flashlight — plus an audible beep for a total of six humane training options.